Decoding device, decoding method, encoding device, encoding method, and program

Abstract

The present technique relates to a decoding device, a decoding method, an encoding device, an encoding method, and a program which can obtain a high-quality realistic sound. The encoding device stores speaker arrangement information in a comment region in a PCE of an encoded bit stream and stores a synchronous word and identification information in the comment region such that other public comments and the speaker arrangement information stored in the comment region can be distinguished from each other. When an encoded bit stream is decoded, it is determined whether the speaker arrangement information is stored on the basis of the synchronous word and the identification information stored in the comment region. Audio data included in the encoded bit stream is output according to the arrangement of the speakers corresponding to the determination result. The present technique can be applied to an encoding device.

The invention claimed is: 
     
       1. A decoding device comprising:
 a decoding unit that decodes audio data included in an encoded bit stream; 
 a read unit that reads information indicating whether extended information is present in the encoded bit stream from the encoded bit stream and reads the extended information on the basis of the read information; and 
 a processing unit that processes the decoded audio data on the basis of the extended information, 
 wherein the extended information includes first information for specifying a downmix coefficient, and further includes second information, 
 the processing unit downmixes the decoded audio data of a plurality of channels on the basis of the downmix coefficient to provide downmixed audio data, and 
 the processing unit further downmixes the downmixed audio data on the basis of the second information. 
 
     
     
       2. The decoding device according to  claim 1 ,
 wherein the extended information includes information for obtaining a gain value which is used to adjust a gain of the downmixed audio data, and 
 the processing unit adjusts the gain of the downmixed audio data on the basis of the gain value. 
 
     
     
       3. The decoding device according to  claim 2 ,
 wherein the extended information includes information indicating whether to use the audio data of a specific channel for downmixing. 
 
     
     
       4. A decoding method comprising:
 decoding audio data included in an encoded bit stream; 
 reading information indicating whether extended information is present in the encoded bit stream from the encoded bit stream and reading the extended information on the basis of the read information; and 
 processing the decoded audio data on the basis of the extended information, 
 wherein the extended information includes first information for specifying a downmix coefficient, and further includes second information, 
 the processing includes downmixing the decoded audio data of a plurality of channels on the basis of the downmix coefficient to provide downmixed audio data, and 
 the processing further includes downmixing the downmixed audio data on the basis of the second information. 
 
     
     
       5. A non-transitory computer-readable storage device encoded with computer-executable instructions that, when executed by a processing device, perform a process comprising:
 decoding audio data included in an encoded bit stream; 
 reading information indicating whether extended information is present in the encoded bit stream from the encoded bit stream and reading the extended information on the basis of the read information; and 
 processing the decoded audio data on the basis of the extended information, 
 wherein the extended information includes first information for specifying a downmix coefficient, and further includes second information, 
 the processing includes downmixing the decoded audio data of a plurality of channels on the basis of the downmix coefficient to provide downmixed audio data, and 
 the processing further includes downmixing the downmixed audio data on the basis of the second information. 
 
     
     
       6. An encoding device comprising:
 an encoding unit that encodes audio data, information indicating whether extended information is present, and the extended information; and 
 a packing unit that stores the encoded audio data, the encoded information indicating whether the extended information is present, and the encoded extended information in a predetermined region and generates an encoded bit stream, 
 wherein the extended information includes first information for specifying a downmix coefficient, and further includes second information, 
 the decoded audio data of a plurality of channels is downmixed on the basis of the downmix coefficient to provide downmixed audio data, and 
 the downmixed audio data is further downmixed on the basis of the second information. 
 
     
     
       7. The encoding device according to  claim 6 ,
 wherein the extended information includes information for obtaining a gain value which is used to adjust a gain of the downmixed audio data, and 
 the gain of the downmixed audio data is adjusted on the basis of the gain value. 
 
     
     
       8. The encoding device according to  claim 7 ,
 wherein the extended information includes information indicating whether to use the audio data of a specific channel for downmixing. 
 
     
     
       9. An encoding method comprising:
 encoding audio data, information indicating whether extended information is present, and the extended information; and 
 storing the encoded audio data, the encoded information indicating whether the extended information is present, and the encoded extended information in a predetermined region and generating an encoded bit stream, 
 wherein the extended information includes first information for specifying a downmix coefficient, and further includes second information, 
 the decoded audio data of a plurality of channels is downmixed on the basis of the downmix coefficient to provide downmixed audio data, and 
 the downmixed audio data is further downmixed on the basis of the second information. 
 
     
     
       10. A non-transitory computer-readable storage device encoded with computer-executable instructions that, when executed by a processing device, perform a process comprising:
 encoding audio data, information indicating whether extended information is present, and the extended information; and 
 storing the encoded audio data, the encoded information indicating whether the extended information is present, and the encoded extended information in a predetermined region and generating an encoded bit stream, 
 wherein the extended information includes first information for specifying a downmix coefficient, and further includes second information, 
 the decoded audio data of a plurality of channels is downmixed on the basis of the downmix coefficient to provide downmixed audio data, and 
 the downmixed audio data is further downmixed on the basis of the second information.